Contact finger and method of making the same



T. E. DROHAN. CONTACT FINGER AND METHOD or MAKING THE SAME.

Patented May 9, 1922.

APPLICATION FILED DE}:- 17, I920- Fig.5.

Fig. 5.

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THOMAS E. DROHAN, 0F SCHENECTADY, NEW YORK, ASSIGNOR TO GENERAL ELECTRIC COMPANY, A CORPORATION OF NEW YORK.

-CONTACT FINGER AND METHOD OF MAKING THE SAME.

T 0 all whom it may concern:

Be it known that I, THOMAS E. DROHAN, a citizen of the United States, residing at Schenectady, in the county of Schenectady, State of New York, have invented certain new and useful Improvements in Contact Fingers and Methods'of Making the Same, of which the following is a specification.

My invention relates to a contact finger.

for making and breaking electric circuits and has for its object the production of a giving it a smooth and even contact surface, and byembedding the heads of the supporting pins in the body of thefinger so that the contact surface is maintained unbroken. My invention provides for the production of contact fingers in a very economical manner.

Other objects andfeatures of my invention will appear in the course of the following specification in which I have shown my invention embodied in concrete form for the purpose of illustration.

In the accompanying drawing Fig. 1 is a perspective view of a contact finger embodying my invention, while Figs. 2, 3, 4 and 5 show the various successive ste s in the making of contact finger in accor ance'with my invention.

Referring to Fig. 2 of the drawing, astrip of soft copper or other conducting metal 10 is cut to the requisite length and holes 11 and'12 punched or bored near the ends thereof. The next step in the making of the contact finger, in which a portion of the metal .strip 10 at each end is bent laterallyg upward and over, is shown in Fig. 3. The portion bent upward at the left end is longer than the portion bent upward at the right end to provide for a curvedcontact or wiping surface 15 as will presently appear. A sufficient angle'is left between the end portions Specification of Letters Patent.

-.in a die and shaped to final Patented May Q), 192-2.

Application filed December 17, 1920. Serial No. 431,522.

and the central portion to permit supporting pins 13 and 14 to be inserted in annpward direction through holes 11 and 12 into positions as shown in Fig. 4;. The piece is now placed in .a die where it is shaped to final form, the end portions being folded downward upon the central portions, as shown in Fig. 5. and the portion to the left of. pin 14 being bent slightly upward to form a curved contact or wlping surface 15. The heads 16 and 17 of the supporting pins are wedged tightly in the holes and between the end portions and the central portion, thereby holding the pins firmly in place. As shown in the drawing the ends of the strip will abut against each other. L

The contact surfaces 15 and 18 will be smooth and even by reason of their engagement under' reat pressure with the surface of the die. y using this method of attaching the supporting pins it is not-necessary to make holesin the surface fore remains unbroken.

In the first operation the stri of metal of desired length may be cut, the holes 18 which thereformed, and the end portions bent upward,

The en porting pins ole is placed form in one as shown in Fig. 3'. are next inserted, and then the operation as shown in Fig. 5.

While I have here shown an embodiment of my invention which is, at present, the best means known tome, I would have it understood that I do not limit my;-invention thereto, since various modifications thereof will suggest themselves to those skilledin the art without departing from the spirit of y in the annexed claims.

What I claim as new and desire to secure invention, the scope of which is set forth by Letters Patent of the United States, is

I 1. A contact member formed of a strip of" 7 metal having a pin passing 'through'a por-- tion thereof, the portions 1? the strip .being folded onto each other.

2. A contact member formed of a strip of metal having a headed pin passing through a ortionthereof, the portions of the strlp belng folded onto each other so as to inclose the head of the in place.

3. A contact member formed an end portion thereof, said end portion being folded over onto the strip so as to inclose pin and hold the pin securely of a strip of .metal havmg aheade'dpin passing through v U the head of the pin and hold the pin securely in place.

- 4;. A contact member formed of a strip of metal having each end provided with a. headed pin passing through the strip and folded "over onto the central portion so as pins and hold the other.

6. The process of'making a contact member out of a strip of metal which consists'in passing alheaded pin through a portion thereof and folding the portions of the strip onto, each'other so .as to inclose the head of the pin and hold the pin securely in place.

7. The process of making a contact member out of a strip of metal which consists in thereof and folding said end portion over onto the strip so as to include the head of the pin and hold the pin securely in place.

8. The process of making a contact memher out of a' strip of metal which consists in passing a headed pin through each .end of the strip and folding the ends over onto the. central portion so'as to inclose the heads of the pins and hold the pins securely in place. In witness, I have hereunto set my hand thisi15th day of December, 1920.

passing a headed pin through an end portion THOMAS E. DR HAN. 

